Cutter-head for gear-cutting machines.



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. CUTTER HEAD FOR GEAR CUTTING MAUHINES.

APPLIOATIOH I'ILHIJ DEC. 23, 1907.

905,084. v Patented Nov. 24, 1908.

2 SHEETS-SHEET 1.

E. JLLEES. CUTTER HEAD FOR GEAR CUTTING mourns. APPLICATION FILED D30.23, 1907.

905,084. Patented Nov. 24,' l908.

2 SHEETS-SHEET 2.

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1n: uoluus PETER: 00-, wAsHmuwN, n. c.

UNITED STATES PATENT onmcn.

ERNEST J. LEES, OF CLEVELANR OHIO, ASSIGNOR TO THE GRANT-LEES MACHINECOMPANY, OF CLEVELAND, OHIO, A CORPORATION OFOHIO.

CUTTER-HEAD FOR GEAR-CUTTING MACHINES.

Specification of Letters Patent.

Patented Nov. 24, 1908.

Application filed December 23,1907. Serial No. 407,672.

To all whom it may concern:

Be it known that I, ERNEST J. LEES, citizen of the United States,resident of Cleveland, county of Ouyahoga, and State of Ohio, haveinvented a new and useful Improvement in Cutter-Heads for Gear-OuttingMachines, of which the following is a specification, the principle ofthe invention being herein explained andthe best mode in which I havecontemplated applying that principle, so as to distinguish it from otherinventions. i

As indicated, the present invention relates to an improved form ofcutter head designed for use particularly in gear cutting machines whichis recognized as an especially diflicult kind of milling work.Obviously, however, such head is equallywell adapted for use in anymilling machine where a universal adjustment of the cutter is necessaryor desirable.

The general subject-matter of this application originally formed a partofmy copending application for gear cuttingmachine, filed September 21,1906, SerialNo.

335,565, from which it has been divided out.

In addition I here show the details of construction involved in themounting of the cutter spindle, which, although the same-as in theoriginal structure, were not thus mi-. nutely illustrated and describedin the application just referred to.

The object of thepresent invention is to provide a universal cutterhead, that, while affording every desired adjustment for the cutting ofspur, worm or spiral gears, will nevertheless be simple in constructionand operation. I I j V I To the accomplishment of these and relatedends, said invention, then, consists of the means hereinafter fullydescribed and particularly pointed out in the claims.

The annexed drawings and the following description set forth, in detailcertain mech anism embodying the invention, such disclosed meansconstituting, however, but one of various mechanical forms in which theprinciple of the invention may be used.

In said annexed drawings: Figure 1 represents a front elevation, withportions shown in section, of a cutter head embodying my severalimprovements; Fig.2 is a horiz'ontal cross section through such cutterhead taken on the line 2-2 Fig. 1;; Fig. 3 is a similar vertical sectionthrough the head;

B and intersecting the same.

and Fig. i is a horizontal section on an enlarged scale of the cutterspindle mounting. In the'aforesaid figures only so much of the frame Aof the machine is shown as is necessary to indicate the manner in whichthe several parts, that constitute the head proper or are directlyconnected therewith, are supported. Such frame portion includes the headstock a in which is mounted the driving shaft B for the cutter head,such shaft being driven at various desired rates ofspeed by means of acone pulley (not shown) or other suitable mechanism.

, To the rear of the head stock and extending in the same generaldirection is a cross member a wherein is mounted the head proper. Thelatter comprises essentially a swiveling support C rotatably mounted ina bearing therefor provided in such cross member a. This swivelingsupport con sists of'a solid cylindrical body 0 provided at one end Withan enlarged face 0 between which and the body proper are formed twospaced shoulders 0 c of diflerent diameters.

'The other end of such body is screw-threadedto receive a nut C, that,for. convenience, is provided with radially extending arms 0 By means ofthis nut, the head is adapted to be drawn longitudinally of its bearingin cross member 0; until the first. c of the spaced shoulders on itsforward end rests solidly against the face of such member a.

In'this way the head is adapted to be secured in any desired angularposition aboutits axis, such axis, as will be evident, lying at rightangles to that of the driving shaft Upon the front, enlarged, face 0 ofthe head are provided two bearings c 0 alined upon a diametrical line,in which bearings is journaled the cutter spindle or arbor D. Suchcutter spindle will obviously lie substantially in the same plane withthe driving shaft B. Mounted upon the cutter spindle intermediatelybetween the two bearings just referred to, is the cutter D, which, inthe machine chosen for illustration, (the same as that shown in myco-pending application),

is of the spiraltype commonly denominated a, hob. Use of this type ofcutter involves a different principle of operation from that involved inthe use of the ordinary, or straight, type of cutter, which principleand its advantages need not here be more than referred to, being fullyset up in my other application wherein a specific modification of suchprinciple is exemplified. Aside from these general advantages, however,a particular advantage in mounting the cutter arises from the fact thatwhere such cutter is in the form of a hob it does not require to becentered with respect to the axial line of the blank. The reason forthis need not be further considered, being obvious, but attention isdirected to the manner in which this feature is adapted to the taking upof wear in the mounting of the cutter spindle in order to secure thesteadiness essential to accurate work.

Referring to Fig. 4, the cutter spindle D will be seen to comprise threealined portions d, (F, (Z of successively increasing diameter. Theterminal portions cl cl are respectively journaled in the bearings c,suitable bushings (Z being of course provided; and upon thecorresponding projecting extremities of the spindle aremounted two lock,or clamp, nuts d and a bevel pinion cl. A washer d is interposed betweenthe innermost of nuts al and the adjacent bearing 0. Upon theintermediate portion (Z of the spindle, which is shorter than the spacebetween bearings 0 0 is keyed the hob D. Such hob is preferably a triflelonger than the portion (Z2 of spindle upon which it is mounted. Upondrawing the spindle to the right, Fig. 4:, by means of nuts d it willaccordingly be seen that the hob may be held with any desired degree oftightness between the inner side of bearing c 'and the offset orshoulder on the spindle between portions d and d Absolute steadiness invrunning may be thus secured. By leaving sufficient clearance betweenpinion (Z and the bearing 0 adjacent thereto, as also betweenintermediate portion d of the spindle and bearing a, provision is easilymade for an indefinite amount of wear without the slightest decrease inthe accuracy of the work turned out, chattering of the tool being justas effectively prevented after a long'period of service as when new. Atthe same time dismounting of the tool is much facilitated, since bysimply removing the nuts (Z the whole spindle, together with pinion dand the hob D, are free to be removed from their mounting on the cutterhead.

Rotatably mounted upon the head C between the cross member a and thesecond of the shoulders 0 wherewith the head is provided, is a beveledgear Z) that serves as an idlerfor the beveled pinion I) mounted uponthe end of the driving shaft B contiguous to the cutter head and thebevel pinion just described as being mounted upon one end of the cutterspindle D. Such bevel gear or idler Z2 has a face wide enough to accom-Vmodate both the pinions, even when the spindle and shaft, whereby theyare respectively borne, are alined. In other words the head may beadjusted about its axis with out any interference between the pinionborne by the cutter spindle and that borne by the drivin shaft. Thesimplicity of the adjustment of the cutter head, whereby the hob D maybe quickly and easily set at any desired angle to the live spindle, isfurther enhanced by the directness of the drive for by avoiding the useof complicated gearing the loss of power is reduced to a small fraction.

Incidentally to the tightening of the hob D in its bearings by theendwise adjustment of the spindle 1) above described, the pinion clmeshing with idler Z) will at the same time be drawn radially inwardwith respect to such idler. This will obviously result in tightening theconnection between the pinion and gear by drawing the teeth of theformer into the narrowing portion of the face of the latter. The oneadjustment is thus seen to simultaneously accomplish two results, takingup not only wear of the hob bearing but also of the teeth of pinion andgear.

Other modes of applying the principle of my invention may be employedinstead of the one explained, change being made as regards the mechanismherein disclosed, pro vided the means stated by any of the followingclaims or the equivalent: of such stated means be employed.

I therefore particularly point out and distinctly claim as myinvention 1. In a device of the character described, the combination ofa driving shaft; a head angularly adjustable about an axis at rightangles to said shaft; a cutter spindle rotatably mounted upon said headand lying in substantially the same plane as said shaft; a bevel gearrotatably mounted upon said head, the face of said gear extending beyondsaid head; and bevel pinions borne by said shaft and spindlerespectively but both in mesh with said gear, the pinion borne by saidspindle being adapted to pass by the one borne by said shaft withoutinterference, as said head is adjusted about its axis.

2. In a device of the character described, the combination with asuitable support; of a driving shaft; a head, provided with a shoulder,mounted in said support so as to be angularly adjustable about an axisat right angles to said shaft; a cutter spindle rotatably mounted uponsaid head and lying in substantially the same plane as said shaft: abevel gear rotatably mounted upon said head between such shoulder andsaid support, the face of said gear extending beyond said head; andbevel pinions borne by said shaft and spindle respectively but both inmesh with said gear, the pinion borne by said spindle being adapted topass by the one borne by said shaft without interference, as said headis adjusted about its axis.

' 3, In a device of the character described,

the combination with a suitable support; of a driving shaft; aheadrotatably mounted in said support so as to be angularly adjustable aboutan axis at right angles to the axis of said shaft, said head beingprovided with two spaced shoulders of different diameters; means adaptedto draw the first of such shoulders against said support to retain saidhead in desired angular position; a cutter spindle rotatably mountedupon said head and lying in substantially the same plane as said shaft;a bevel gear rotatably mounted upon said head between such secondshoulder and said support; and bevel pinions borne by said shaft andspindle, respectively, the pinion borne by the latter bein adapted topass by the other without inter erence.

4. I11 a device of the character described, the combination with asuitable support; of a driving shaft; a head rotatably mounted in saidsupport so as to be angularly adjust able about an axis at right anglesto the axis of said shaft, said head being provided with two spacedshoulders of difierent diameters; a nut threaded upon the rear end ofsaid headland adapted to draw the first of such shoulders against; saidsupport; two diametrically alined bearings upon the. front end of saidhead; a-spindle ournaled insaid bearings; a hob'mounted upon saidspindle between said bearings; a bevel gear rotatably mounted upon saidhead between such second shoulder and said support; and bevel pinionsmounted upon the end of said shaft and spindle, respectively, the pinionborne by thelatter being adapted to other without interference.

5. In a device of thecharacter described, the combination of two alinedbearings, a spindle mounted in said bearings and longitudinallyadjustable with respect to the same, and a cutter mounted upon saidspindle between said bearings, said spindle being formed with a shoulderdisposed to bear against said cutter and press the latter against one ofsaid bearings upon longitudinal adjustment of said spindle. l

6. In a device of the character described, the combination of twoalinedabearings, a spindle mounted in said bearings and longie tudinallyadjustable with respect to the same, said spindle'comprising twoportions of unequal diameters of which portions the smaller extendsbetween said bearings, and a cutter mounted upon such smaller spindleportion, the shoulder between such portions bearing against one side ofsaid cutter and adapted upon longitudinal adjustment of pass by theportion bearlng against one side of said outter and adapted uponlongitudinal adjustment of said spindle to press the other side of saidcutter against the adjacent bearing.

a 8; In a device of the character described, the combination of twoalined bearings, a

spindle mounted in said bearings and longitudinally adjustable withrespect to the same, said spindle comprising three portions ofsuccessively increasing diameter, the intermediate portion lying whollybetween said bearings and the terminal portions being journaled in saidbearings, respectively, and a hob mounted upon such intermediate spindleportion, said hob being longer than such portion and the shoulderbetween such portion and the adjacent larger portion bearing against oneside of said cutter and adapted to press the other side of the sameagainst the adjacent bearing.

9. In a device of the character described, the combination with asuitable support; of a driving shaft; a head, formed with a shoulder,mounted in said support so as to be angularly adjustable about an axisat right angles to said shaft and provided on its face with two alinedbearings; a spindle mounted in said bearings and longitudinallyadjustable with respect to the same; a cutter ter and press the latteragalnst one of said bearings upon longitudinal adjustment of saidspindle; a bevel gear rotatably mounted upon said head between suchshoulder and said support; and bevel pinions borne by said shaft andspindle respectively, the pinion borne by the latter being adapted topass by the other without interference.

Signed byme this 16th day of December, 1907.

ERNEST J. LEES.

Attested by E. R. Rom), 'JNO. F., OBERLIN-

